Scanning confocal fluorescence microscopy has emerged as the critical technology for the resolution of sub-cellular organellar trafficking and localization. Resolution of subcellular events in live cells as well as fixed cells requires high resolution imaging best accomplished through confocal microscopy. Furthermore, confocal microscopy allows imaging of intracellular event in live cells. As confocal microscopy has become the mainstay of intracellular cell biological imaging, demands on confocal instrumentation at Vanderbilt have radically increased. We therefore are seeking to obtain funding for an Olympus FV1000 scanning confocal microscope with a WeatherStation live cell stage attachment. This instrumentation will provide critical resources for high-resolution fluorescence microscopy. In addition, it will provide unique capabilities for live cell investigations including enhanced experimental approaches to Fluorescence Recovery after Photobleaching (FRAP), imaging in the ultraviolet range, and the ability to utilize photoactivatable probes for dynamic live cell imaging. All of these features will enhance the ability of the epithelial biologists and cell biologists in the Major User Group to perform investigations in the three dimensional organization and dynamics of living cells. Relevance: The study of intracellular membrane vesicle and cytoskeletal dynamics has increasingly received greater interest among investigators as the focal point for understanding aberrations in intracellular physiology that underlie an area of pathologies including cancer, inflammatory diseases and infectious pathogenesis in epithelia. Indeed, understanding intracellular trafficking events may be central to the development of specific therapies for a number of maladies ranging from viral infections to cancers. Confocal fluorescence microscopy, especially in its uses for the study of living cells, holds the key to performing all of these studies. PHS 398/2590 (Rev. 09/04) [unreadable] [unreadable] [unreadable]